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Just bought a 1979 southwind. Engine ran good and had lots of power. Then.. I took the car to the garage to have the right side manifold exhaust leak fixed. On way to garage I filled up the gas tank. After picking up the RV, on way home I noticed a lack of power on hills and bopping. Plenty of power on level roads from 50mph and up. I have started troubleshooting. Can't find in vacuum leaks. Guage shows about 14#. Sparkplug wired looks okay. Cleaned out the distributor, it looks okay.
454 firing order, switched it and now it won't start at all.....used 1-8-4-3-6-5-7-2, before it would start but nothing now. Looses power, lugs down backfires. P-30 chasis....90-91 Winnebago MH......any help would be appreciated. Could it be a diff sized engine on that P-30 chasis? If so what? Where can I find firing order for the larger engines that may be applicable? Stumped in WA! Thanks ahead of time!
Just bought a 1979 southwind. Engine ran good and had lots of power. Then.. I took the car to the garage to have the right side manifold exhaust leak fixed. On way to garage I filled up the gas tank. After picking up the RV, on way home I noticed a lack of power on hills and bopping. Plenty of power on level roads from 50mph and up. I have started troubleshooting. Can't find in vacuum leaks. Guage shows about 14#. Sparkplug wired looks okay. Cleaned out the distributor, it looks okay.
Mike, I don't know what they repaired but you migh take a look to see if they put the right gasket on the manifold. If they put a smaller opening gasket on it would restrict the flow and lose lot's of power. The popping could be caused by the exhaust sensor calling for a leaner mixture due to the backpressure caused by the smaller gasket.
Just bought a 1979 southwind. Engine ran good and had lots of power. Then.. I took the car to the garage to have the right side manifold exhaust leak fixed. On way to garage I filled up the gas tank. After picking up the RV, on way home I noticed a lack of power on hills and bopping. Plenty of power on level roads from 50mph and up. I have started troubleshooting. Can't find in vacuum leaks. Guage shows about 14#. Sparkplug wired looks okay. Cleaned out the distributor, it looks okay.
Every thing else being equal, tow things could be the problem. The plug wire for the two rear cylinders on the right bank---the one they worked on---could be running parallel and right next to each other, a definite no-no, as this can cause induced ignition in #7 when # 5 fires---firing order is 1-8-4-3-6-5-7-2, odd cylinders are the left bank, # 1 nearest the front of engine. Your condition could be that the # 5 & # 7 plug wires are swapped.14" of mercury vacuum at hot idle is pretty low. If you've got a good hot idle, then you don't have a vacuum leak,. I'd put the vacuum gauge on it with enough hose to bring it to where you can see it as you drive. If you get low vacuum at road speed, then you've got, 1. cam timing has jumped a tooth or so---easily checked with a timing light--each tooth= 7 1/2 degrees of ignition timing change. 2. The shop dropped something down into your exhaust system and now it's restricted, or the pipe got pinched somehow.
Thanks for all the suggestions. I've learned a lot chasing my problems. What seems to have corrected my problems was the spark plug wires. After changing the gas filter and getting no improvement, I pulled off to the side of the road and seperated the #4 and #8 wires, any cross over of the 2 wires was made at about 90 degrees. Then the RV drove like it had a tune up. still a couple of pops during the half hour drive. Tomorrow I'll get a new set of wires and pay close attention to how I arrange them. Again thanks to all and to the suggestions. M Every thing else being equal, tow things could be the problem. The plug wire for the two rear cylinders on the right bank---the one they worked on---could be running parallel and right next to each other, a definite no-no, as this can cause induced ignition in #7 when # 5 fires---firing order is 1-8-4-3-6-5-7-2, odd cylinders are the left bank, # 1 nearest the front of engine. Your condition could be that the # 5 & # 7 plug wires are swapped.14" of mercury vacuum at hot idle is pretty low. If you've got a good hot idle, then you don't have a vacuum leak,. I'd put the vacuum gauge on it with enough hose to bring it to where you can see it as you drive. If you get low vacuum at road speed, then you've got, 1. cam timing has jumped a tooth or so---easily checked with a timing light--each tooth= 7 1/2 degrees of ignition timing change. 2. The shop dropped something down into your exhaust system and now it's restricted, or the pipe got pinched somehow.
Yes, there are usualy two wires on each side that fire next to each other. As previously stated, I believe it is 8-4 and 5-7. They need to be arranged so they to do touch each other or are to close. Use good wires, not cheap ones. I run Jacobs 8mm. This give a better shielding.
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